The present invention relates, in general, to safe and arming devices and, more particularly, to safe and arming devices for munitions.
There are numerous safe and arming devices known in the art, such as U.S. Pat. No. 4,470,351 developed by the same inventor and assigned to Motorola Inc. Most existing safe and arming devices are either mechanical or electromechanical in nature. The mechanical versions utilize centrifugal gears which are retarded by runaway escapement damping devices which act as speed governors. These devices provide delay in terms of revolutions of the projectile after muzzle exit.
Electromechanical safe and arming devices operate on fixed time delays which provide long arming distances for high speed projectiles and short delays for slow speed projectiles.
While counting the turns of a weapon can provide constant calibers arming for a given weapon, regardless of launch velocity, a different caliber delay results when fired from a weapon having a different bore diameter or different twist.